Hello, I am wanting code that replaces newlines or carriage returns with the charachter \n. The following code will do this: 
use strict;

$_=<<'_quote_';
hai xtest "aa xx 


aax" baix "xx"
x "axa\"x\\" xa "x\\\


\\"x" ax
xbai!x
_quote_

print "Original:\n", $_, "\n";

s/
(
    (?:
        # at the beginning of the string match till inside the quotes
        ^(?&outside_quote) "
        # or continue from last match which always stops inside quotes
        | (?!^)\G
    )
    (?&inside_quote)  # eat things up till we find what we want
)
\r?\n   # the thing we want to replace
(
    (?&inside_quote)  # eat more possibly till end of quote
    # if going out of quote make sure the match stops inside them
    # or at the end of string
    (?: " (?&outside_quote) (?:"|\z) )?
)

(?(DEFINE)
    (?<outside_quote> [^"]*+ ) # just eat everything till quoting star
+ts
    (?<inside_quote> (?:[^"\\\r\n]++|\\.)*+ ) # handle escapes
)
/$1\n$2/xg;

print "Replaced:\n", $_, "\n";

[download]
However, I want to be able to do this for a file that I read in (*.csv). For example, if I use the follwing to read the same file into $_, it does not work: 
my $file="testdata.csv";
open(FILE, $file) or
    die "Can't open $file: $!\n";
select((select(FILE), $/ = undef)[0]);
$_=<FILE>

[download]
Any ideas? And, no I am not able to use the Perl packages Spreadsheet::**** Here, testdata.csv is this business: hai xtest "aa xx aax" baix "xx" x "axa\"x\\" xa "x\\\ \\"x" ax xbai!x

In reply to Regular Expressions - replacing newlines and carriage returns inside quotes by PRyanRay

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